ref: f93bc27cbd73b33ac30122d2ca64aab63ce0e327
dir: /jbig2_image_pbm.c/
/* jbig2dec Copyright (c) 2002 artofcode LLC. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. $Id: jbig2_image_pbm.c,v 1.12 2002/08/15 14:54:45 giles Exp $ */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include "os_types.h" #include <stdio.h> #include <ctype.h> #include "jbig2.h" #include "jbig2_image.h" /* take an image structure and write it to a file in pbm format */ int jbig2_image_write_pbm_file(Jbig2Image *image, char *filename) { FILE *out; int error; if ((out = fopen(filename, "wb")) == NULL) { fprintf(stderr, "unable to open '%s' for writing", filename); return 1; } error = jbig2_image_write_pbm(image, out); fclose(out); return (error); } /* write out an image struct as a pbm stream to an open file pointer */ int jbig2_image_write_pbm(Jbig2Image *image, FILE *out) { /* pbm header */ fprintf(out, "P4\n%d %d\n", image->width, image->height); /* pbm format pads to a byte boundary, so we can just write out the whole data buffer NB: this assumes minimal stride for the width */ fwrite(image->data, 1, image->height*image->stride, out); /* success */ return 0; } /* take an image from a file in pbm format */ Jbig2Image *jbig2_image_read_pbm_file(Jbig2Ctx *ctx, char *filename) { FILE *in; Jbig2Image *image; if ((in = fopen(filename, "rb")) == NULL) { fprintf(stderr, "unable to open '%s' for reading\n", filename); return NULL; } image = jbig2_image_read_pbm(ctx, in); return (image); } /* FIXME: should handle multi-image files */ Jbig2Image *jbig2_image_read_pbm(Jbig2Ctx *ctx, FILE *in) { int i, dim[2]; int done; Jbig2Image *image; int c; char buf[32]; /* look for 'P4' magic */ while ((c = fgetc(in)) != 'P') { if (feof(in)) return NULL; } if ((c = fgetc(in)) != '4') { fprintf(stderr, "not a binary pbm file.\n"); return NULL; } /* read size. we must find two decimal numbers representing the image dimensions. done will index whether we're looking for the width of the height and i will be our array index for copying strings into our buffer */ done = 0; i = 0; while (done < 2) { c = fgetc(in); /* skip whitespace */ if (c == ' ' || c == '\t' || c == '\r' || c == '\n') continue; /* skip comments */ if (c == '#') { while ((c = fgetc(in)) != '\n'); continue; } if (isdigit(c)) { buf[i++] = c; while (isdigit(buf[i++] = fgetc(in))) { if (feof(in) || i >= 32) { fprintf(stderr, "pbm parsing error\n"); return NULL; } } buf[i] = '\0'; sscanf(buf, "%d", &dim[done]); i = 0; done++; } } /* allocate image structure */ image = jbig2_image_new(ctx, dim[0], dim[1]); if (image == NULL) { fprintf(stderr, "could not allocate %dx%d image for pbm file\n", dim[0], dim[1]); return NULL; } /* the pbm data is byte-aligned, so we can do a simple block read */ fread(image->data, 1, image->height*image->stride, in); if (feof(in)) { fprintf(stderr, "unexpected end of pbm file.\n"); jbig2_image_free(ctx, image); return NULL; } /* success */ return image; }